The 87-year-old man lives in neighboring Phu Tho Province with five other members of his family.
In the past month neither he nor anyone else in his house went outside their neighborhood in Khai Xuan Commune, Thanh Ba District.
He has no underlying diseases.
On August 11 he visited E Hospital, a general public facility in Hanoi, for a health check after having a fever and muscular pain in the right waist.
Two days later he was admitted to the hospital and diagnosed with pneumonia.
He then tested positive for Covid-19 on Wednesday.
The hospital stopped receiving patients from Wednesday night and has isolated 50 people who had come into close contact with the man.
It was disinfected immediately.
Vietnam’s Covid-19 tally has risen to 994 with 25 deaths.
Since July 25, when local transmission resurfaced in Da Nang, there have been 654 cases, 514 linked to the central city.
Globally, more than 22.5 million people have been infected with the new coronavirus and almost 790,000 have died.